Cyanazine is a member of the triazine family of herbicides that is based on the tri-nitrogen aromatic heterocycles. Other members of this family include atrazine, simazine, prometon, propazine, metribuzin, and hexazinone. These chemicals act as inhibitors of photosynthesis, and their herbicidal activity depends on the ability of tolerant plants to degrade or metabolize the parent triazine nucleus, whereas the susceptible plants are unable to do so. Cyanazine is used primarily on corn, however the EPA has severely restricted the use of this chemical because of its teratogenicity and because it also has been detected in groundwater.